1. Field of the Invention
This invention relates to anti-theft systems for portable objects, and, more particularly, to such systems adapted specifically for personal computers.
2. Description of the Related Art
It is widely known that theft of laptop and desktop personal computers is a serious problem and is increasing annually.
Security devices for computers, such as cables and locks which physically attach a computer to a work station are common. So are computer software programs which require the user to enter a pre-programmed password into the computer before it may be used. It is also common to attach a device to a component, such as a floppy disk drive, which renders the computer inoperable until removed with the correct key or code (see U.S. Pat. Nos. 5,400,622 and 5,660,065).
Motion detecting security systems or devices for small personal items, such as suitcases, attache cases, and skis are also widely known (see U.S. Pat. Nos. 4,155,079, 4,272,763, and 5,660,065).
Recently, an integrated alarm system for portable computers has been developed which, when armed, sounds an alarm or disables the computer upon unauthorized movement of the computer from a stationary position. The alarm system includes one or more motion sensors and/or micro switches that provide a signal indicating that the portable computer has been moved from a stationary position or that the computer is being opened from its closed position (see U.S. Pat. No. 5,760,690).
Also, a security system specifically designed for laptop computers has been recently developed which includes a security device internally connected to the computer. The security system also includes a remote unit which, together with the security device, acts as a vicinity switch which signals an alarm when the security device and remote unit are no longer within a specific range. In one embodiment, the system includes a motion detecting alarm internally connected to the computer,(see U.S. Pat. No. 5,757,271).
A major drawback with motion detecting alarm systems is that they can only be used when the computer is stationary. When the computer is being transported, which is the most common situation when theft occurs, the motion detecting alarm must be inactive. Another drawback with motion detecting alarm systems is that depending upon the sensitivity of the motion detecting switches, the computer may be gently moved by a thief without activating the motion detecting alarm system.
A major drawback with internally connected vicinity switch systems is that they require one of the bays or slots inside the laptop computer. Further, they require the computer's system be turned on when armed, which makes them dependent on the laptop's battery.
Ideally, a security system for a laptop computer should prevent theft while the computer is both stationary and while being transported. Further, it should be selectively affixed externally to the computer and not require the use of a bay or slot inside the computer. Still further, it should not be dependent on the computer's system being activated or the computer's battery.